WO1991008946A1

WO1991008946A1 - Method and apparatus for power transmission to a surface driving propeller mechanism and use of a turbine between the driving engine and propeller mechanism

Info

Publication number: WO1991008946A1
Application number: PCT/SE1990/000823
Authority: WO
Inventors: Jörgen SELMER
Original assignee: Cps Drive A/S
Priority date: 1989-12-13
Filing date: 1990-12-12
Publication date: 1991-06-27
Also published as: NO179968C; JPH05501688A; NO922339L; FI922717A0; FI103780B; DE69012586T2; AU646653B2; ATE111406T1; EP0505429A1; DE69012586D1; EP0505429B1; AU6918591A; NO922339D0; NO179968B; FI103780B1; CA2071197A1; CA2071197C; JP3191218B2; US5312277A

Abstract

A method and a device for power transmission from a motor having a supercharging assembly, particularly a supercharged Diesel-engine (7), to a gear (3) with a surface water driving propeller mechanism (4), mounted in a boat of the planing variety and preferably with a large propeller with a large pitch, in which a turbine coupling (10), which can be filled to a variable extent, is mounted between the supercharged motor (7) and the gear (3), the motor being designed to drive the pump portion (15) of the turbine coupling (10) and the turbine portion (17) of the turbine coupling (10) being connected to the input shaft (6) of the gear (3), the turbine coupling (10), when the boat is started, being emptied completely or partially, in such a way that it is at least partially disconnected from the gear, the motor being accelerated to such a speed, that the supercharging assembly of the motor (7) is connected, the turbine coupling being quickly filled with hydraulic medium, the propeller mechanism (4) being influenced by the substantially maximum output of the motor, caused by the supercharging assembly, and when the boat has reached its planing speed the motor speed in the desired way being reduced and/or the extent of filling of the turbine coupling being reduced, yet not to a lower speed than that the boat will be propelled with a speed which is somewhat larger than the planing limiting speed. The invention also relates to the use of a turbine coupling in planing boats having gears of the above-described variety.

Description

METHOD AND APPARATUS FOR POWER TRANSMISSION TO A SURFACE DRIVING PROPELLER MECHANISM AND USE OF A TURBINE BETWEEN THE DRIVING

ENGINE AND PROPELLER MECHANISM

TECHNICAL FIELT

The present invention generally relates to driving sys¬ tems for boats having so called surface water driving propeller assemblies, and the invention more particu- larly relates to such a driving system, in which the driving motor is a motor with a supercharging assemb¬ ly, particularly a supercharged Diesel-motor (turbo- Diesel) or a motor having a compressor supercharger.

A surface water driving propeller assembly is a type of boat gear, in which the gear is mounted in the stern of preferably planing boats and in which the propeller as¬ sembly with its gear body projects essentially horizon¬ tally backwards (when the boat is planing) outside the stern, and which drives a propeller with an essentially straight shaft. Gears of this type are mounted in such a way, that the gear housing, when the boat is driven at speeds above a certain minimum speed, which corre¬ sponds to the lowest planing speed, is substantially pa- rallel with the water surface and close to the water surface and in which the propeller assembly with its propeller dips into the water with only about half its height. Some propeller blades are then positioned in water, whereas other propeller blades are being venti- lated in the air above the water surface. Propellers designed for this type of gear are consequently larger and/or have a larger pitch than conventional underwa¬ ter-working propellers, usually at least a 15 % larger diameter and pitch, because only some of the propeller blades exert a propulsion power below the water sur¬ face, and also the propellers must rotate considerably slower than conventional underwater-working propellers in order to attain the best driving conditions. Various examples of gears with surface water driving propel- lers are shown in European patent specification 37.690 (Arneson) or in Swedish patent accplications 8804295-7 and 8804296-5 (Thiger) .

When the boat is immobile and before it when driven has accelerated to its planing speed, all the propeller as- sembly and the better part of the gear body are positio¬ ned below the water surface, and a very large force from the motor is required, if the motor is to be able to accelerate the boat up to its planing speed, atwhich speed the propellers will be able to start working in the desired way, particularly because the propeller as¬ sembly is considerably larger and has a larger pitch than conventional underwater-working propellers.

Gears with propeller assemblies of the surface water- driving type are very different from underwater-driving propellers, i.a. since the propeller in the planing speed works in air as much as 50-70 % and is considerably lar¬ ger and usually has a considerably larger pitch than the corresponding underwater-working propellers and since the propeller drives the boat through a pressure force from the rear side of the propeller, while con¬ ventional underwater-working propellers propel the boat through a suction force on the front side of the propel¬ ler in substantially the same way as a sailing boat, when the wind comes ahead to port, is propelled through the suction force from the front side of the sail. This is the main reason for the absence of a cavitation and a suction downwards of air from the water surface as far as a surface water-driving propeller goes, which is quite common as to conventional underwater-workingpro¬ pellers. Thus, it is possible as to surface water-dri¬ ving propellers, already when the boat is immobile, to exert an initial force on the propeller, which corre¬ sponds to a maximum torque from the motor. In this way a boat with a surface water-driving propeller can be accelerated very strongly, and in practice such pro¬ peller assemblies, in comparison with underwater-dri- ving propellers, prove to attain a speed increase of as much as 30-40 %.

When motors, particularly Otto-engines, without turbo- charging assemblies are used, the required large ini¬ tial force can often be obtained through a large gas input, but when using driving motors provided with su¬ percharger assemblies such as turbo- or compressor- charge-assemblies, particularly supercharged Diesel- engines (turbo-Diesel engines) , problems arise, which have so far been very difficult to solve. The Diesel- engines to be sure normally have a fairly small speed range and a low maximum top speed and have a relatively weak acceleration capacity from low speeds. Super- charged Diesel-engines also to be sure do not obtain their higher power range, made possible by means of the turbo-assembly, before the supercharger assembly has been connected, and this is not done before the speed is relatively high. Thus, when Diesel-engines are used, particularly supercharged Diesel-engines, in boats with gears of the above-mentioned surface water-driving type, the view has so far been that it is necessary to use an oversized engine, which is able to accelerate the boat to its planing speed within a reasonable pe- riod of time, or that it is necessary to use other, maybe expensive and complicated solutions in order to obtain a high driving motor output already from the start.

THE STATE OF THE ART

Also as far as underwater-driving propellers go, the propeller to be sure working constantly and in its en¬ tirety against water, the corresponding problem may arise but not to the same extent as in the case of sur- face water-driving propellers, where the propeller works against water only from the immobile condition of the boat and up to its planing speed, while the ac- tive surface of the propeller against water when the speeds are higher than the planing speed is only 40-60 % of the total propeller-surface, while the remaining part of the surface works in air and substantially with- out any reaction requirement. As far as such underwater- driving propellers go, the propeller proportionally be¬ ing smaller than surface water-driving propellers and allowed to work with a considerably higher speed than surface water-driving propellers, the above-mentioned problems could be solved by feeding air downwards to or allowing air to be sucked downwards to the propeller, in order to make the propeller "spin" and with a main¬ tained high speed accelerate the boat to its planing speed. In certain cases this problem has also been solved by equiping the boat with an undersized propel¬ ler in order to allow a "spinning", when a cavitation and an air suction downwards take place.

Swedish document 451.449 (Brunswick Corporation) , laid open to public inspection, describes a system designed to increase the acceleration of a boat by connecting between the motor and the gear a torque-boosting hydro- dynamic torque converter. Such a torque converter allows a certain slippage between the pump and the turbine, often a slippage of almost 20 %, which allows an acce¬ leration of the motor, before the propeller starts to drive fully, and in this way the motor will already from the start of the acceleration cycle have a speed, which at least to some extent has approached.the high- est output-speed of the motor. The slippage in the torque converter is limited i.a. by the use of statio¬ nary guide rails and by the shape of the pump and tur¬ bine blades and it allows only a certain limited mo¬ tor speed increase, before the successively increased hydraulic pressure in the torque converter makes the propeller drive with a substantial force. However, due to the comparatively large slippage of almost 20 % bet- ween the pump and the turbine and the guide rails respec¬ tively a complete motor output on the propeller cannot be attained, and due to the risk of overheating etc. al¬ so such a slippage cannot be allowed for an extended period of time. Thus, the hydrodynamic torque converter in the above-mentioned public inspection-document is according to this document designed with a lockable me¬ chanical coupling, a so called lock-up clutch, which is connected when the motor reaches a certain predeter¬ mined speed and is disconnected when the motor speed is lower than this predetermined speed.

A device of the above-described type has some draw¬ backs, which make it unserviceable for gears with sur¬ face water-driving propellers and for motors of the type, which requires an almost maximum speed, before the motor output starts being transmitted to the pro¬ peller, e.g. motors having a surcharge assembly, so called turbo-motors, and this is particularly true for Diesel-engines but also for Otto-motors. In boats with such motors, for which the motor output has been calcu¬ lated with regard to the maximum output at a high motor speed, said device cannot be used at all, since this high motor speed cannot be obtained before the driving force is transmitted to the propeller. Also, the de¬ vice is complicated and expensive, there is a great risk of overheating and an overheating of the hydrau¬ lic medium due to the extensive slippage, special pump assemblies are required for a connection and a discon- nection of the lock-up clutch, and there is a risk of slippage also in the lock-up clutch at high motor speeds and outputs.

THE INVENTION in accordance with the present invention the above- described problem can be solved in a surprisingly simp¬ le and very efficient way, namely by connecting between the motor, e.g. the turbo-Otto-engine or the turbo-Die¬ sel-engine and the gear a simple turbine coupling of a type, which comprises only a pump wheel and a turbine wheel, which turbine coupling can be filled and emp- tied respectively successively in a short period of time, also during a driving condition, and which tur¬ bine coupling can be driven in any filling condition, substantially between 0 and 100 %, and which in its emptied condition brings about a substantially total disconnection between the motor and the gear, andwhich in its filled condition causes anextremely small slip¬ page between the motor and the gear, normally merely a slippage of 1.5 - 3 %, which slippage is so insigni¬ ficant that it does not cause any overheating problems.

A turbine coupling is fundamentally different from a torque converter in several respects, i.a. since the turbine coupling works because of the kinetic energy of the hydraulic medium, while the torque converter works because of the pressure energy of the hydraulic medium; the turbine coupling has a very minor slip¬ page, usually only about 1.5 - 3 %, whereas the torque converter usually has a slippage of at least 20 %, and consequently it usually must be combined with a lock- coupling in order to make it serviceable; the turbine coupling brings about a direct hydraulic torque trans¬ mission because of a simple rotary liquid flow, where¬ as the torque converter brings about a power amplifi¬ cation with a gear reduction because of a complex curved liquid flow, brought about by the blades of the pump portion and the turbine portion, which blades are designed in a complicated way, and because of the use of stationary guide rails. A torque converter cannot at all solve those problems, which were the cause of the present invention, whereas a turbine coupling solves those problems in a surprisingly efficient way. By using such a simple turbine coupling it is possible to take the following steps:

- When starting the motor the turbine coupling is comp¬ letely emptied, and consequently the motor works sub- stantially without any resistance;

- The motor is accelerated to its maximum or almostmax¬ imum speed, the surcharge assembly or turbo-assembly be¬ ing connected;

- The turbine coupling is only then filled up with hyd- raulic medium, a torque being transmitted, to the pro¬ peller very quickly, which torque corresponds to almost the entire motor output, and consequently the boat acce¬ lerates rapidly to its planing speed;

- The motor speed is subsequently reduced in the de- sired way as long as the boat is driven at a speed fas¬ ter than the planing speed.

The filled turbine coupling works as an almost direct¬ ly acting coupling, and it can stay filled until the boat speed is reduced to the displacement speed, when the acceleration-method may be repeated.

A surface water-driving propeller should, as has been mentioned above, be large, have a large pitch and be driven with a relatively low speed and consequently it is suitable to mount a reduction gear, possibly a reduction gear having a built-in reversing gear, bet¬ ween the turbine coupling and the gear. The reduction gear suitable is designed in such a way, that the pro- peller, when the motor runs at full speed, has a speed of about 1000 - 2000 r/m or rather 1,200 - 1,500 r/m. The reversing gear suitably is a mechanical gear or alternatively can be designed as a hydrodynamical torque converter, which is directly connected to the hydrodynamic coupling and which is used solely as a reversing gear. When the boat is run in the forward direction, the torque converter is not used at all and by-passed. By means of such a device it is possible to directly from a full speed forwards connect the torque converter to a full output backwards, the high motor speed being maintained.

Also, by using a hydraulic coupling with a variable fil¬ ling and a surface water-driving propeller mechanism, which besides has propeller blades with a variable in¬ clination, it is quite possible to completely dispense with a reversing gear and to connect the driving motor directly to the turbine coupling, e.g. via a gear belt. When the hydraulic coupling has been emptied, it does not transmit any motor output to the gear and the pro¬ peller then works as an ideal freewheel coupling, the propeller being immobile. An additional advantage of using propellers having blades with a variable incli¬ nation is that when the inclination of the propeller blades is varied, the pitch will vary and consequent¬ ly also the pulling power of the propeller and the load of the motor respectively, which is particularly advantageous for boats, which carry loads, the weight of which varies considerably. Also, by means of this device an additionally improved driving economy canbe attained. Also, it is possible, if propeller blades with a variable pitch are used, to run the boat at any low speed, e.g. down to 1 knot or lower, and conse¬ quently the boat can be used also for purposes, e.g. for fishing, which it normally is impossible to do with boats, which often has a minimum idling speed of 4 - 5 knots or even higher.

The reduction of the motor speed to a suitable gear speed for the propeller mechanism can e.g. be achieved by means of a belt coupling or in a corresponding way. EMBODIMENTS

The invention will now be described in more detail, re¬ ference being made to the accompanying drawings. Fig. 1 shows fragmentarily a so called planing boat, which is provided with a gear and a surface water-driving propel¬ ler, shown in a lateral view, the boat having a dis¬ placement position. Fig. 2 shows in a correspondingway the same boat in its planing position. Fig. 3 shows the propeller in the driving unit schematically, when the boat is immobile, viewed from behind; and Fig. 4 shows in a corresponding way the propeller from behind, when the boat is running with a planing speed. Fig. 5 shows schematically an embodiment of a driving unit according to the present invention, and Fig. 6 shows another em¬ bodiment of the driving unit. Fig. 7 shows a vertical section through a possible example of a turbine coup¬ ling having a reversing gear, which device advantage¬ ously can be combined with the invention. Fig. 8 shows how the invention can be used jointly with gears having surface water-driving propellers of type "Arneson"; and Fig. 9 shows a detail of the same device. Fig. 10 shows how the invention can be used, when a plurality of motors are combined, mutually coupled in a row, after each other, to one common longitudinal shaft.

Thus, Fig. 1 shows a boat, in stern 1 of which and close to bottom 2 of which a gear 3 having a surface water-driving propeller 4 is mounted. The stern has in this case an inclination of only about 20-30 and is adapted to a special type of gear, a so called CPS- gear. Gear 3 extends with a gear unit 5 substantially straight outwards and rearwards from stern 1, and it is with an inner clutch 6 connected to a driving motor 7, in the present case an inboard motor, particularly a Diesel-engine having an overcharge unit (turbo-Die¬ sel) . Between clutch 6 and gear unit 5 the gear is pro- vided with a device 8 designed to pivot the gear in the horizontal plane and to tilt gear unit 5 in a vertical plane (tilting) . Motor 7 transmits its driving force to propeller 4 by means of a substantially straight drive shaft, which includes two universal joints and a con¬ ventional "slide"-coupling in order to allow a transmis¬ sion of force also when the gear unit is steered and tilted. For the rest the gear is designed in a known way and will not be described in more detail.

When the boat is immobile and before it has been acce¬ lerated to a certain minimum speed, propeller 4 is posi¬ tioned completely below the water surface, as is shown in Fig. 1 and 4. However, as the speed increases, the boat is elevated, particularly its stern, and conse¬ quently gear 3 and its propeller 4 are elevated to¬ wards the water surface, and when the boat has accele¬ rated to a planing speed, only a portion 9 of the ac¬ tive propeller surface dips into the water (see Fig. 3) . This active surface 9 is maintained substantially un¬ changed also at higher speeds of the boat.

When the boat is started, all the shown five propeller blades are working against the water and a very large driving power from the motor is required to accelerate the boat to its planing speed, particularly since the propeller blades on surface water-driving gears are sub¬ stantially larger and usually also have a considerably steeper pitch than the propeller blades on the corre- sponding conventional underwater-driving propellers, e.g. on gears of the so called Z-type or the INU-gear- type. Up to the moment when the boat has been accelera¬ ted to its planing speed, as is shown in Figs. 2 and 4, the reaction force from the water decreases successive- ly, and a proportionately smaller amount of force for the propulsion of the boat is required. The acceleration of the boat to its planing speed has, as has been mentioned above, created problems with al¬ ready known devices of this type, particularly when Diesel-engines are used, which usually have a relati- vely small speed range, and above all when surcharged Diesel-engines (turbo-Diesel-engines) are used, which as is known require a comparatively high speed before the surcharge unit is connected and the Diesel-engine reaches its higher power range by means of the turbo- unit.

This problem is solved according to the invention, as is shown schematically in Figs. 5 and 6, by connecting a seemingly not required but actually most valuable turbine or turbine coupling 10 between the output shaft of motor 7 and gear 3.

A turbine coupling is a simple and service-reliable hyd¬ raulic coupling with a variable filling and it can be driven with any degree of filling between 0 and 100 %. When the filling is 0 %, the pump blades and the tur¬ bine blades do not touch each other at all and the slip¬ ping between the blades is in this case practically 100 %. Thus, the turbine coupling creates practically no resistance at all against an acceleration of the motor. When the filling is complete, the slippage of the tur¬ bine coupling is very small, normally only 1.5 - 3 %. Thus, by filling the turbine to any degree of filling between 0 and 100 % any required slippage can be ob- tained, and the coupling is a most flexible coupling, which is particularly useful for marine purposes.

Thus, turbine coupling 10 has the advantage that the input partwith the pump blades can be accelerated to a high speed with an empty turbine, before the filling of the coupling is started and the output of the turbine blades starts offering a substantial resistance corre- sponding to the water reaction force on the propeller blades. Thus, surprisingly enough we found that it is entirely possible, by using a conventional turbine coupling, to attain a quick and efficient accelera- tion of a boat having surface water-driving propel¬ lers and equipped with one or several non-oversized surcharged Diesel- or Otto cycle-engines from an immo¬ bile position to its planing speed, which has not been possible with already known devices. Thus, this is pos- sible by already when the boat is immobile accelerate the Diesel-engine to such a speed that the surcharge unit is connected before the filling of the turbine coupling is commenced, the water reaction force against the propeller or the propellers reaching such a large value, that difficulties otherwise would have been ex¬ perienced when accelerating the boat to its planing speed. An additional advantage of using a turbine coupling having a variable filling is that it is pos¬ sible to continuously and constantly cool the hydrau- lie medium for the coupling, every risk of a super¬ heating being eliminated.

A practical test:

In a practical test two different driving systems on the same boat and the same motors were examined. The boat was a 35 feet planing plastic boat equipped with two turbo-Diesel-engines, mounted in parallel, eachwith 340 hp and with a maximum speed of 2,000 r/m. The en¬ tire boat, including motors and gear, weighed 10 tons. A. A conventional straight shaft with underwater-dri¬ ving propellers:

In this first test the boat was equipped in a conven¬ tional way with straight shafts and underwater-driving propellers, which in order to accelerate the boat to its planing speed had an optimal diameter of 15" and a pitch of 17".From the starting condition the gas input had to be done comparatively slowly in order to avoid an overload of the motor and a discharge of black Diesel-smoke caused thereby, and only after 20-30 se¬ conds had the boat been accelerated to its maximum speed, the motor speed reaching 2.40 r/m and the speed with the existing load being 28 knots.

B. Hydraulic coupling as well as a gear with surface wa¬ ter-driving propeller:

In a second test with the same boat and the samemotors as in case A the boat was equipped with gears with surface wa- ter-driving propellers (see the above-mentioned known publications ) as well as with a turbine coupling, made by Voith, between each motor and each gear. Each propel¬ ler had in this case a diameter of 29 " and a pitch of 39" ; and the hydraulic coupling was provided with a conventional three way valve, by means of which the coup¬ ling quickly could be filled and emptied respectively, to any suitable degree of filling. Between the turbine coupling and the propeller shaft was used a reduction gear (2:1) of the gear belt variety. In all the follow- ing test runs the boat was started from an immobile con¬ dition on an open water surface, the wind and wave con¬ ditions being the same as in case A, and was accelera¬ ted to its full speed. Bl. In a first trial run a) the hydraulic coupling was emptied completely of oil, the slipping increasing to almost 100 %, b) the motors were accelerated to a maxi¬ mum speed, which was 2,600 r/m; c) in direct connection with this the three way valve to the turbine coupling was opened up and consequently the turbine couplingwas filled completely. The motor speed decreased during the acceleration, when the turbine coupling was being comp¬ letely filled, to not lower than 2,300 r/m and increased again at full speed to about 2,400 r/m, which corre¬ sponds to a propeller speed of 1,200 r/m. It was ob- served that the boat in this case was accelerated very strongly and yet the motors emitted no black Diesel- smoke whatsoever, and the boat had already after about 10-12 seconds accelerated to its full speed, which in this case was 38 knots, namely 10 knots or 36 % faster than in case A. When the boat had accelerated to above its planing speed, the motor speed and the speed of the boat could be lowered as we saw fit to almost the pla¬ ning limit speed of the boat.

B2. In a second trial run the boat was started with a completely filled turbine coupling and with the twoDie¬ sel-engines at full speed. In this instance the motor speed increased to only 600 r/m and the boat could not be accelerated to a higher speed than 6 knots. A thick black Diesel-smoke filled the environment. B3. In a third trial run the boat was started with its turbine coupling filled to about 50 % and also in this case with the two motors at full gas input. In this case the boat dragged itself slowly up to about 18 knots, a thick Diesel-smoke being emitted during all the accele¬ ration step. The acceleration phase up to 18 knots took about 30-40 seconds. Only after a complete filling of the hydraulic coupling was the speed increased to 38 knots.

The tests showed that it is entirely possible to, in a very brief period of time, accelerate a planing boat, under the above described circumstances, to its full speed; that this can be done without any practical and technical problems or drawbacks; that the acceleration can be done without any overload of the motors, with¬ out any overheating of the turbine coupling, and with- out any black Diesel-smoke being emitted; that the acce¬ leration can be done without any oversizing of the mo¬ tors; that it is possible to use an ideal non-under¬ sized propeller; and above all that the driving unit allows a surprisingly large increase in the efficien- cy of the device.

The driving unit suitably includes a reduction gear, which reduces the motor speed, transmitted by means of the turbine coupling, to a suitable propeller speed, and also the driving unit ought to include a reversing gear in order to accomplish deceleration and reversing functions.

In Fig. 5 it is shown how between turbine coupling 10 and gear 3 a mechanical combined reduction and rever¬ sing gear 11 has been mounted, and how clutch 6 of gear 3 has been connected directly to gear 11.

In Fig. 6 another embodiment for the same purpose is shown. In this case the reversing gear has been mounted in a unit connected to the turbine coupling, and the re- duction gear comprises a belt coupling 12, which extends between the output shaft of turbine coupling 10 and the input shaft of gear 3, the belt disks on the coupling and the gear respectively determining the gear ratio between motor 7 and gear 3.

Turbine 10 can be any known type of turbine and as an example the turbine couplings manufactured by the com¬ pany Voith can be mentioned, e.g. the couplings of type TP or TD, which can be filled to a variable degree.

In Fig. 7 is shown, as a feasible example of a useful device, a turbine coupling in a vertical section, which turbine coupling T in this specific case is connected to a reversing coupling in the form of a hydrodynamic torque converter M and a reduction gear R of the gear belt variety. Turbine coupling T is connected to ba¬ lance wheel 12 on motor 7 via an elastic force trans¬ mission disk 13, which is secured by screws to rotary interior casing 14 of the pump ring in the coupling, in which pump blades 15 are mounted. Pump blades 15 are fed with a pressure medium from a hydraulic pump (not shown) through a schematically shown conduit 16, which is connected to a valve, designed to fill and empty re¬ spectively the turbine coupling. The hydraulic medium issuing from pump blades 15 influences turbine blades 17 through the mass flow, which are connected to output shaft 18 of the coupling. Output shaft 18 of the turbine coupling is in this case designed with a gear belt-reduc¬ tion gear R, which comprises a gear belt disk 19, which by means of a gear belt 20 cooperates with a second lar¬ ger gear belt disk 21, which in its turn is mounted on output shaft 22 of the reduction gear. This output shaft 22 is directly connected to input coupling 6 of gear 3.

In order to allow a deceleration and reversing function boat gears are normally provided with a conventional mechanical reversing gear or combined reduction and re¬ versing gear, as is indicated with gear 11 in Fig. 5. However, in the embodiment shown in Fig. 7 is a hydrau¬ lic reversing gear 23 in the form of a known type of hydrodynamic torque converter M connected to turbine coupling T and to reduction gear R. The reversing gear works in the opposite rotational direction against the hydraulic coupling and it is activated, solely during re¬ verse motion, whereas it is completely disconnected du¬ ring forward motion, which is done exclusively by in- fluencing the turbine coupling. The reversing gear is fed with pressure medium from a hydraulic pump (not shown) through a schematically shown conduit 24. Con¬ duits 16 and 24 are connected to a multiple-way valve, which empties one of the two conduits when the other one is fed with the pressure medium and vice versa, and in this way the turbine coupling and the reversing gear respectively can be connected according to what is de¬ sired and without being influenced by the other part.

In Figs. 8 and 9 is shown an application of the inven¬ tion, in which the motor-turbine coupling-assembly accor¬ ding to the invention, combined with a gear of the so called Arneson-type(shown in EP 37.690), is used in an ordinary boat body, the stern of which is inclined in relation to a horizontal plane by 83 and the stern can have another inclination than perpendicular to the out- put shaft of the motor assembly. In this case the follow¬ ing steps are taken:

- The motor assembly is provided with a U-shaped support 25, which extends backwards and is attached to reduction gear 26, and which serves as a rear motor support, de- signed to suspend motor 27 between a front motor bracket 28 and rear support 25;

- With the aid of the axis of the output shaft of the gear box a small hole is drilled in stern 29 concentri¬ cally in relation to the output shaft of the motor; - An extension tube (not shown) is placed around the output shaft of the gear box in order to form a guide tube for the ensuing machining;

- Their machining consists of arranging milling tools in two steps on the guide tube, and in the first step is from the inner side a plane circular contact sur¬ face milled on the inner side of the stern, exactlyper¬ pendicular to the output shaft of the gear box, and in the second step is from the outer side a similar plane circular contact surface milled, care being taken to mill off as small an amount of material as possible, i.e. to make the inner milling tool mill off material only between the upper edge of the central hole and to make the outer milling tool mill off material only above the lower edge of the central hole; - The milling tool and the extension tube are removed;

- A rubber packing 30, whole or divided, having a U- shaped cross-section, is inserted into the central hole and covers in this way the outer and the inner side as well as the intermediate transverse edge; - A guide bushing 31 is inserted into rubber packing 30 and its inner side corresponds to the mounting dimen¬ sion of the mounted gear 32; and - Gear 32 is inserted into guide bushing 31 and adjacent the output shaft of reduction gear 26 and is fastened by means of screws to stern 29 in the usual way.

This method allows a mounting of the shown gear on boats, in which the motor perhaps has been positioned in vary¬ ing angles in the boat body, or in which the stern has a rather varying inclination.

Fig. 10 shows another application of the invention, in which three motor units 33, 34, 35, each comprising a mo¬ tor 36, a turbine coupling 37 and a reduction gear 38, have been mounted in alignment after each other andbeen connected to a common longitudinal shaft 39, which cons- titutes the input shaft of gear 40. In the same way an optimal number of motor units can be connected to out¬ put shaft 39. The output shaft can be positioned any¬ where below or, as is shown in Fig. 10, beside the mo¬ tor units. A device of this type has a plurality of ad- vantages:

- It is possible to position the motor units in a suit¬ able way, e.g. distributed along the entire length of the boat or in another way, and achieve a perfect weight distribution in the boat; - An extended but comparatively thin motor unit system is obtained, which can be mounted also in narrow spaces, e.g. close to the keelson of the boat;

- It is possible to use in a certain motor unit system an optional number of the mounted motors, because each motor unit can be entirely disconnected by a simple emp¬ tying of turbine coupling 37, the turbine coupling for¬ ming a perfect freewheel having almost no resistance;

- It is possible, when the load is minor, to disconnect one or several motors by simply emptying the turbine coupling and to drive the boat by means of only the rest of the motors;

- It is possible to use simple and inexpensive standard motors in order to assemble a strong motor unit system instead of mounting just one large and powerful motor, which usually prooves to be considerably more expensive than the multiple integrated motor units; - The service and maintenance will be inexpensive and simple;

- The access to each motor unit for service and mainte¬ nance is satisfactory;

- It is possible, in a simple way and by means of simple lifting tools, to lift a motor out of the boat and send it to a factory or shop for service or repair, the boat in the meantime using the remaining motors;

- It is possible to connect motors of different types and having different outputs to the common output shaft without the motors influencing each other in any way; and

- It is possible, by varying the degree of filling of the turbine couplings, to adjust the propulsion condi¬ tions to all kinds of occuring circumstances; etc.

Thus, the present invention relates to a method of trans¬ mitting power from a motor having an overload assembly, particularly an overloaded Diesel-engine, a so called turbo-Diesel-engine, to a gear with a surface water- driving propeller mechanism and in a planing motor boat, in which method:

- A turbine coupling, preferably having a degree of filling which can be varied from 0 to 100 %, is connec¬ ted between the motor and the gear and the pump element of the turbine coupling is driven by means of the turbo-motor;

- The turbine element of the coupling is connected to the input shaft of the gear;

- The turbine coupling is completely or partly emptied before a starting;

- The motor is accelerated to such a high speed, with¬ out any considerable resistance from the water, which acts on the propeller mechanism, that the overload assembly of the motor is connected; and - The turbine coupling is filled completely or partly and consequently the motor will, with its preferably full output, achieved by means of said overload as¬ sembly, act on the propeller via the turbine coupling.

The invention also relates to a device designed to car¬ ry out the method and in a driving system comprising a motor, particularly a Diesel-engine, with an overload assembly and an outboard gear with a surface water- driving propeller mechanism having a large and compa¬ ratively slowly rotating propeller, a turbine coupling, which can be filled in a variable way, having beenmoun- ted between the turbo-motor and the gear with the pro¬ peller mechanism, which turbine coupling can be emptied and refilled so quickly, that the turbo-motor can be accelerated to such a speed, that the overload assemb¬ ly has been connected, before any important reaction force has been obtained from that water, which is in¬ fluenced by the propeller-mechanism.

The present invention also relates to the use of atur¬ bine coupling in driving means designed for planing boats and comprising a motor, particularly a Diesel- engine, with an overload assembly and an outboard gear having a surface water driving propeller mecha¬ nism and in which the turbine coupling can be emptied and refilled so quickly, that the motor can be acce- lerated to such a speed, that the overload assembly has been connected, before any considerable reaction force from the propeller mechanism, influenced by the water, has been transmitted to the motor via the tur¬ bine coupling.

Claims

CLAIMS :

1. A method of transmitting power from a motor with a supercharge assembly or a compressor assembly, particu- larly a supercharged Diesel-engine (7) , to a gear (3) with a surface water-driving propeller mechanism (4) , mounted in a boat of the planing variety and preferab¬ ly with a large propeller having a large pitch, c h a r a c t e r i z e d in that - a turbine coupling (10) , which can be filled to a variable extent, is mounted between the supercharged motor (7) and the gear (3) ;

- the motor will drive the pump portion (15) of the tur¬ bine coupling (10) , and the turbine portion (17) of the turbine coupling (10) is connected to the input shaft (6) of the gear (3) ;

- the turbine coupling (10) is emptied completely or partially, when the boat is started, and consequently it is at least almost fully disconnected from the gear; - the motor speed is accelerated to such an extent, that the supercharge assembly of the motor (7) is con¬ nected;

- the turbine coupling is filled quickly with hydrau¬ lic medium, and consequently the propeller mechanism (4) is actuated by the output of the motor, which sub¬ stantially is at a maximum thanks to the influence of the supercharge assembly; and

- when the planing speed of the boat has been reached, the motor speed can be reduced to the desired extent and/or the degree of filling of the turbine coupling reduced, but only to such an extent, that the boat will be propelled with a speed slightly above the pla¬ ning limiting speed.

2. A method according to claim 1, c h a r a c t e ¬ r i z e d in that the motor, when the boat is accele¬ rated from its immobile condition, is accelerated to its maximum speed, after which the turbine coupling (10) will be filled completely and in this way, with a very small slippage, will work as a substantially unelas- tic coupling.

3. A method according to claim 1 or 2, c h a r a c t e ¬ r i z e d in that the propeller has a substantially lar¬ ger size and a substantially larger pitch than the si¬ zes and pitches of the corresponding underwater-driving propellers.

4. A method according to claim 1, 2 or 3, c h a r a c ¬ t e r i z e d in that a reduction gear (11;12) is con¬ nected between the turbine coupling (10) and the gear (3) , preferably a reduction gear, which, when the mo¬ tor speed is at a maximum, results in a propeller speed of 1,000 - 2,000 r/m or preferably 1,200 - 1,500 r/m.

5. A device designed to carry out the method according to any of claims 1-4 for a driving system for planing boats, comprising a motor with a supercharge assembly or a compressor assembly, particularly a supercharged Diesel-engine (7) , and a gear (3) of the special type, which has a surface water driving propeller mechanism (4), c h a r a c t e r i z e d in that a turbine coupling (10) is provided between the supercharged mo¬ tor (7) and the gear (3) with the surface water dri¬ ving propeller mechanism (4) and can be filled to a variable extent, preferably between 0 and 100 %, and the turbine coupling is provided with means designed to quickly empty and fill respectively it in such a way, that the motor, substantially without being in¬ fluenced by the propeller mechanism (4) , can be acce- lerated to a speed, at which the supercharge assembly is connected, particularly to a maximum speed, after which the turbine coupling quickly is filled, the pro- peller mechanism (4) being actuated with a maximum or almost maximum motor output.

6. A device according to claim 5, c h a r a c t e r i z e d in that the propeller (4) has a considerably larger size and has a larger pitch than the size and the pitch of corresponding underwater-driving propellers at optimal driving conditions.

7. A device according to claim 6, c h a r a c t e r i z e d in that a reduction gear (11) is mounted between the tur¬ bine coupling (10) and the gear (3) , particularly a re¬ duction gear, which gives the propeller a maximum speed of 1,000 - 2,000 r/m or preferably 1,200 - 1,500 r/m.

8. A device according to claim 7, c h a r a c t e r i z e d in that the reduction gear (11) is connected to a mecha¬ nical (11) or a hydraulic (M) reversing gear.

9. A device according to claim 7, c h a r a c t e r i z e d in that the reduction gear (11) is a belt coupling, par¬ ticularly a gear belt coupling, mounted between the tur¬ bine coupling (10) and the gear (3) (Fig. 7) .

10. A device according to claim 8, c h a r a c t e ¬ r i z e d in that the hydraulic reversing gear is a torque converter (M) , which is used exclusively as a reversing gear, and in that the device includes means designed to automaticly disconnect the torque conver¬ ter (M) , as soon as the turbine coupling (10) has been filled with hydraulic medium (Fig. 7) .

11. A use of a turbine coupling (10), which can be filled to a variable extent, particularly between 0 and almost 100 %, and has a very minor slippage, when it is completely filled, particularly a slippage of at a maximum 1.5 - 3 %, as well as is provided withmeans designed to quickly empty and fill respectively this turbine coupling

- in a driving device for planing boats (1,2);

- which driving device comprises a motor (7) with a supercharge assembly, particularly a supercharge Die¬ sel-engine, a so called turbo-Diesel-engine;

- and a gear (3) of the type, which projects substan¬ tially straight backwards from the boat;

- and which has a surface water driving propeller me- chanism (4) ;

- and in which the turbine coupling (10) is connected between the supercharged Diesel-engine (7) and the gear

(3); and

- in which the turbine coupling (10) and the filling and emptying means for the same are such, that they allow an acceleration of the supercharged motor (7) to such a speed, that the supercharge assembly is con¬ nected, particularly at a maximum motor speed, before any substantially reaction force from the propeller mechanism, which is influenced by the water, has in¬ fluenced the Diesel-engine (7) via the turbine coup¬ ling (10) , and that the turbine coupling after that quickly is filled, with the result that the propeller mechanism (4) during all the acceleration process is influenced by the high motor output, caused by the su¬ percharging assembly.

12. A use of a turbine coupling in accordance with claim 11 in a gear, - in which the propeller mechanism is changed down, the surface water driving propeller rotating at a maximum with 1,000 - 2,000 r/m or preferably 1,200 - 1,500 r/m and;

- in which the propeller has a considerably larger size and a larger pitch than the size and pitch of the corresponding underwater-driving propellers.

13. A use of a turbine coupling in accordance with claim 11 or 12 - combined with a reversing gear in the form of hydrodynamic torque converter (M) , designed in such a way that the torque converter is disconnected comp¬ ly letely, as soon as the filling of the turbine coupling is commenced and the turbine coupling starts driving the pump in a forward motion (Fig. 7) .

14. A use of a turbine coupling in accordance with 10 claims 11, 12 or 13 in a motor installation,

- comprising a plurality of units of identical or different motors, distributed in a row after each other along the longitudinal direction of the boat from its stern to its bow;

15 - in which each motor unit includes a turbine coupling (37), which can be filled to a variable degree andean be emptied completely;

- and a drive coupling with or without a reduction gear (38) ;

20 - in which all the motor units (33-35) in the row of motor units are connected to a common output shaft (39) , which is connected to the input of the gear (40) with the surface water driving propeller mechanism; and

- in which the common output shaft (39) extends between 25 or beside said motor units (Fig. 10) .